125i/128i/130i power output

[Drawn05]

Hi. I have been trawling through many 1er forums for the last year and a half, interested in the power outputs of the n52 engine 1ers.

Now, I have not read every post but it seems that the actual reason behind the differing power outputs of the same engine in different models has eluded many.

I have a 125i that I enjoy but really feel that it has been choked as far as its potential is concerned. I have paid close attention to the idea that the 3X intake manifold is the difference between the 125/128 and the 130 but..

After looking closely on realoem.com, there appears to be many differences between the 125/128 and 130 (and no difference with the intake). For instance the torque converter, exhaust and primary/rear silencer, drive train, output shaft, Diff/drive output etc. are all different just to name a few that I noticed.

I have very limited mechanical knowledge, but has anyone here tried replacing the 125/8 parts with 130 parts? Are they even readily available? Do you think it would work/ be too expensive? Considering the amount of differning parts that I noticed between the 125/8 and 130 i assume the power must come from more than just an ecu remap.

I have an auto, so I was curious to know if changing my 125 torque converter to the 130 would improve the power output? I beleive that the auto trans are the same across the models. I am sorry in advance if this subject has been done to death.

[AW128i]

To further complicate it, there are actually two versions of the 128i in the U.S., N52 and N51, with the latter being compliant with the lower emissions standards that some states require. I'm not sure if it's been determined to be fact or not, but there is speculation that the N51 has the 3-stage intake manifold, as well as other modifications, to account for the power reduction that the additional catalysts and their placement have on the engine.

EDIT: Just checked realoem.com and it seems the speculation is correct; the intake manifold part #'s between the N51/N52 are different and the N51 incorporates some sort of adjuster on the intake.

[Alext]

The 130i has a different intake manifold I believe.

[Dackelone]

Also... I think on the 130i engine it is a Direct Injection motor. While on the 125/128 its the old cylinderhead port injection. I think that is why the 130i also make a few more HP.

[AW128i]

Originally Posted by Dackelone

Also... I think on the 130i engine it is a Direct Injection motor. While on the 125/128 its the old cylinderhead port injection. I think that is why the 130i also make a few more HP.

I don't think BMW has any naturally-aspirated direct injection 6-cylinders, do they??

[banglemangle]

Originally Posted by AW128i

I don't think BMW has any naturally-aspirated direct injection 6-cylinders, do they??

banglebungle

[Drawn05]

Originally Posted by Alext

The 130i has a different intake manifold I believe.

Yes I have heard much about that but looking at the part numbers for the entire intake manifold system, they are exactly the same for the 125/128 and 130. I would assume that if there were physical differences between them they would at least have differing parts numbers. Unless this is controlled by the software.

[Alext]

check out realoem.com for part numbers and differences.

[chylld]

someone tried to fit the 130i's intake manifold to a 125i and only barely got 130i inputs. our cars already have the necessary plugs for the manifold but getting the software to play nice is the tricky part.

you can get a 125i to over 130i power levels (i.e. 200kw) using a couple of german tunes, ds-motorsport and wintertuning. the risk of course is that you have to send your ECU half-way around the world and pray that it gets back safely! (let alone working at all)

it's been said by many a 135i owner, but i will also echo their opinion - the best bang for your buck performance improvement would be to sell the 125i and get a second-hand 135i. they're infinitely more tunable and if the 135i stock power levels are good enough for you, then you also have the comfort of full manufacturer's warranty. (actually if you tune it you'd probably still have warranty, magnus morrison act etc.)

or you can trade in for a golf R APR stage 1 tune = 0-100 in 4.7 secs, stage 2 in 4.3 secs

[Jeef Beef]

Originally Posted by AW128i

I don't think BMW has any naturally-aspirated direct injection 6-cylinders, do they??

The 3.0L N52 270hp is direct injection.

[jksgoh]

Originally Posted by Jeef Beef

The 3.0L N52 270hp is direct injection.

i thought they made none DI (i.e. N52) and DI engines (i.e. N53). and i also thought the N53's weren't sold here.

[AW128i]

Originally Posted by Drawn05

Yes I have heard much about that but looking at the part numbers for the entire intake manifold system, they are exactly the same for the 125/128 and 130. I would assume that if there were physical differences between them they would at least have differing parts numbers. Unless this is controlled by the software.

125i: 11617559523
130i: 11617559523
128i (N51): 11617559523
128i (N52): 11617559524

The N51 is the super ultra-low emissions version of the N52 that I previously mentioned is sold in some U.S. states. It's interesting to know that the 125i, 130i, and the N51 128i share the same intake manifold, but the N52 128i has a different manifold. Also looking at realoem.com, you may note that the 125i, 130i, and N51 128i all incorporate two "adjusters" on the manifold and the N52 128i does not. This certainly suggests that the 125i, 130i, and N51 128i all have an adjustable manifold and the N52 128i does not.

Originally Posted by Jeef Beef

The 3.0L N52 270hp is direct injection.

Interesting. Did some research and it seems BMW introduced the N53 in Europe sometime in 2007 and yep, it has direct injection, though it doesn't have Valvetronic.

[Dackelone]

Originally Posted by AW128i

I don't think BMW has any naturally-aspirated direct injection 6-cylinders, do they??

Only "some" BMW models in Europe are D.I. (NA). (I think the 328i and 330i and 130i motors) No models in the US market. I think BMW is too concerned with carbon buildup and sludge buildup. The only reason why they have them over here (in Germany) is bc next year (2011) all cars must be euro norm Euro-5. Soon, E-6 will be the best lowest poluting emission level. This is in adition to CO2 per grams/km traveled. This is how the taxes are calculated on registered cars in Europe now.

I was watching a German tuning show last week. They were talking about the little sports car called Weissman. It uses a e46 M3 engine. That engine was only a Euro-4 motor... but Weissman mods the engine so that it qualifies for the Euro-5 emission rating. I thought that was interesting. New small sports cars (Weissman) made in Germany powered by M-power engines. And able to meet strindgent new Euro-5 emissions.

[Drawn05]

Originally Posted by chylld

someone tried to fit the 130i's intake manifold to a 125i and only barely got 130i inputs. our cars already have the necessary plugs for the manifold but getting the software to play nice is the tricky part.

you can get a 125i to over 130i power levels (i.e. 200kw) using a couple of german tunes, ds-motorsport and wintertuning. the risk of course is that you have to send your ECU half-way around the world and pray that it gets back safely! (let alone working at all)

it's been said by many a 135i owner, but i will also echo their opinion - the best bang for your buck performance improvement would be to sell the 125i and get a second-hand 135i. they're infinitely more tunable and if the 135i stock power levels are good enough for you, then you also have the comfort of full manufacturer's warranty. (actually if you tune it you'd probably still have warranty, magnus morrison act etc.)

or you can trade in for a golf R APR stage 1 tune = 0-100 in 4.7 secs, stage 2 in 4.3 secs

Thanks for the reply but I don really need to upgrade to the 135i that badly or create a 400rwkw monster. I am quite happy to have a NA engine but I just think that it isnt living up to its potential. If that same engine can produce at least an extra 40kw for the 130 than I wouldnt mind getting a little closer to that. I would of bought a 130 had it come in coupe rather a hatchback only.

Its funny that here in aus there arent any tuners that could give more than 15kw whereas DS motorsports believes the full 200kw is possible with just a remapped ecu. As I have said, I am not very mechanically minded but wouldnt the different torque converters be a source for hp/kw loss in the 125i? And besides if a full 200kw remap was possible and as the 125i torque converter isnt rated as highly as the 130i one, wouldn't it need being replaced anyway, as its risk of failure would increase?